Since March 26, the progress of the bypass adit excavation has been very slow.

by cndjs on 2010-03-27 23:40:14

The translation for "大大大大大大ddddddddddddddddddddddddd" would mostly keep the same form in English as it appears to be a repetitive string of characters without specific meaning. So, in English, it would be: "Big big big big ddddddddddddddddddddddddd". However, this is a very unusual and non-standard expression, so its actual meaning might depend heavily on context.